(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A small dam of triangular shape as shown is made from concrete. Find the stresses on the foundation at A and B. Assume concrete and water weighs 25kN/m^3 and 10kN/m^3

(All dimensions in the attached picture are in metres)

2. Relevant equations

sigma = force/cross sectional area

bending stress = M.y/I (I'm thinking we might need to use this)

centroid of triangle is a 1/3 from the high side

3. The attempt at a solution

I'm pretty much all over the place as I have no direction. So pretty much all that I've jotted down as just been ideas that lead nowhere.

I labeled the top of the dam as C

Area ABC = 6m^2

W (distributed loading for concrete) = 25 x 6 = 150kN/m

One idea I was told was to find the bending stress at point A and B, take I to be value of the dam, find the Max M of the dam and the value of centroids to be 1m for point B and 2m for point A.

I'm not too sure if my FBD is correct because I think it may be a fixed support but this is what my friend thinks it will look like. See below.

I just need the right direction or the right idea. I'm thinking that I have to try and convert those weights into a force, just not sure how to work out the force for the water.

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# Mechanics of solids question from my mid semester exam

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